Joint Patch Near-Field Holography

Traditional wave superposition method can't reconstruct the sound field precisely because of the absence of the equivalent source configuration information. A method named Joint Patch Near-field Holography (JPNAH) is proposed based on the statistically optimal near-field acoustical holography and the wave superposition method. The basic idea is that the fictitious sources' location essential to the wave superposition method can be decided by the statistically optimal near-field acoustical holography, and then complex sound field will be reconstructed by the wave superposition method with high efficiency and precision. Besides the reconstruction of the patch sound field, the JPNAH has many other virtues. Firstly, the JPNAH technique is not sensitive to the sound source outside the patch area. Secondly, compared to the NAH, the JPNAH performs better in the low frequency range. Finally, it is possible to achieve a real-time mapping of the complex sound field by using the JPNAH. Numerical simulations were performed based on a single-pulse-ball model; and also motor experiments were carried out in a semi-anechoic chamber. Both of numerical simulations and experiments show that the JPNAH can be used to reconstruct the sound field radiated from a complex sound source.